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Unit 4 Periodic Table

Elements are arranged in order according to increasing atomic number
Periods go across and Groups go down
Different types of elements: Alkali metals, Alkaline Earth Metals, Metalloids, Transition Metals, Non Metals, Noble Gases

Trends in Periodic Table
Electronegativity: attraction for electrons in chemical bond (higher the value, stronger the attraction.
As you move across the period, electronegativity increases. As you move down the groups, it decreases

Ionization Energy: amount of energy needed to remove loosely bound electron from gaseous atom
Increases from left to right and decreases as you go down a group.

Atomic Radius: decreases left to right and increases down a group

Shielding Effect: decrease in attraction to outer electrons to nucleus
Increases as you go down periodic table, stays the same as you move across the periodic table

Electron Affinity: same trends as electronegativity

4 different orbitals
SPDF
S- shows the shape of the orbital, can only hold a maximum of 2 electrons, 7 energy levels with S configuration

P- Nonmetals and noble gases (last row), the elements on the left and bottom of the P orbital block have less characteristics of metals

D- located in the center of the periodic table, transition metals

F- fourth energy level, can hold 14 electrons, no shape to describe them

Quantum Numbers: Describe which orbital each electron is in
Principal (n) – size of orbital (can’t be zero )
Angular (l) – Shape ( 0 , 1 , 2 , 3 )
S p d f
Magnetic (m) Quantum Number – orientation in space ( -1, 0, 1)
Spin Quantum Number – spin of axis ( - ½ , ½ )

Questions:
  1. What is the electron configuration for Aluminum?
  2. Which has higher electron affinity: Silicon or Oxygen?
  3. Which type of element is each of the following (alkaline, transition…) ?
Magnesium Uranium Fluorine

Websites:
http://www.chem.tamu.edu/class/majors/tutorialnotefiles/trends.htm
http://www.angelo.edu/faculty/kboudrea/general/quantum_numbers/Quantum_Numbers.htm
http://www.hhs.homewood.k12.al.us/~kreaves/Periodictable.htm